[moderation] [fs?] KCSAN: data-race in do_readv / do_sendfile (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 27102b38b8ca Merge tag 'v6.14-rc3-smb3-client-fix-part2' o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=113ccdb0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e4bb91ef214703b
dashboard link: https://syzkaller.appspot.com/bug?extid=1f20c07d6b67019d3c63
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/380836a668b1/disk-27102b38.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5a61ecb19311/vmlinux-27102b38.xz
kernel image: https://storage.googleapis.com/syzbot-assets/dafdda94e604/bzImage-27102b38.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1f20c0...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in do_readv / do_sendfile

write to 0xffff888119ffc430 of 8 bytes by task 6421 on cpu 0:
do_readv+0x127/0x220 fs/read_write.c:1075
__do_sys_readv fs/read_write.c:1158 [inline]
__se_sys_readv fs/read_write.c:1155 [inline]
__x64_sys_readv+0x45/0x50 fs/read_write.c:1155
x64_sys_call+0x2c34/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:20
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888119ffc430 of 8 bytes by task 6420 on cpu 1:
do_sendfile+0x113/0x660 fs/read_write.c:1314
__do_sys_sendfile64 fs/read_write.c:1424 [inline]
__se_sys_sendfile64 fs/read_write.c:1410 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
x64_sys_call+0xfbd/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:41
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0x000000000000000e

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6420 Comm: syz.4.1074 Not tainted 6.14.0-rc3-syzkaller-00295-g27102b38b8ca #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.